1. Field of the Invention
The present invention relates to an improved speaker enclosure and, in particular, concerns a speaker enclosure seamlessly manufactured out of lightweight, sound absorbing materials.
2. Description of the Related Art
Speaker enclosures of the prior art are typically made out of a semi-rigid material, such as plywood, and have a box-like shape. The front side of the speaker enclosure includes a baffle which has several openings in which the diaphragm portion of the speaker is positioned so that sound can emanate out from the speaker enclosure. This describes the typical speaker enclosure that is used in many different applications including speakers for home use and speakers for use at music concerts.
One difficulty that occurs in many large prior art speaker enclosures is that they are very heavy. In particular, the large speakers that are used, for example, in music concerts require large speaker enclosures. Generally, the enclosures have to be made out of fairly thick material to support the weight of the speakers. Consequently, speaker enclosures can become very heavy. As can be appreciated, the heavier the speaker enclosure, the more difficult it is to move and support the speaker enclosure. In some instances, the increased weight results in difficulties in mounting these enclosures.
For example, it is often desirable to mount speakers over the heads of the performers and audience at musical concerts. However, heavy speaker enclosures pose a risk of the speaker enclosures breaking loose from their supports and falling on the performers or the audience. To minimize this risk, heavy duty supports are needed to securely retain the speaker enclosures. It can be appreciated, however, that these supports increase the cost of installing the speaker enclosures and can also increase the time required to mount the enclosures.
A further difficulty that results from constructing speaker enclosures out of materials such as plywood is that these materials often degrade the sound performance of the speaker. Ideally, all of the sound that is produced by the speaker should emanate outward from the diaphragm of the speaker away from the speaker enclosure. However, there are typically some errant sound waves which travel inward into the speaker enclosure.
A semi-rigid material, such as plywood, has a tendency to vibrate in response to these inwardly travelling errant sound waves. These vibrations can result in distortion of the sound produced by the speakers. To minimize these vibrations, sound engineers often have to place materials inside of the speaker enclosure to dampen the errant sound waves and minimize the vibrations. However, the speaker enclosures are typically configured so as to maximize the output of the speakers and placing extraneous materials and objects inside the speaker enclosures can further result in degradation of the sound performance of speaker.
To address these problems, some speaker enclosure designers have built enclosures for speakers out of materials that are lightweight and could, conceivably, absorb some errant sound waves. One example of such an enclosure is shown in U.S. Pat. No. 3,804,195 which discloses a loudspeaker enclosure made out of corrugated sheets of material. The corrugated sheets of material include hollow portions. Each of these sheets are joined to each other in a box-like configuration. Another example is U.S. Pat. No. 4,811,403 which discloses a lightweight loudspeaker enclosure that uses a rigid lightweight honeycombed material in part of the speaker enclosure.
While the weight characteristics and sound performance of the speaker enclosure disclosed in the U.S. Pat. No. 3,804,195 and the U.S. Pat. No. 4,811,403 may be improved by the use of the corrugated material, there will still be vibrations of the speaker enclosure due to the fact that there are seams which join each of the pieces of the enclosure. The errant sound waves induce vibrations at the seams and joints between the individual materials and thereby reduce the overall sound performance or efficiency of the speakers. Further, the enclosures disclosed in both these patents still have some surfaces and materials which vibrate in response to errant sound waves and thereby reduce the overall efficiency and sound performance of the speakers.
Hence, there is a need in the art for a lightweight speaker enclosure which minimizes distortion of the sound signal produced by the speakers as a result of errant sound waves in the speaker enclosure. To this end, there is a need for a speaker enclosure that is made out of a composite of strong lightweight materials that have sound absorbing qualities. Further, this speaker enclosure should also be as seamless as possible to minimize the sources of distortion of the sound signals.